Shock absorber



May 18, 1948.

M. H AHN SHOCK ABSORBER Filed March 7, 1946 2 Sheets-Sheet l Oil WW 3m May 18, 194 s.

SHOCK M. HAHN ABSORBER Filed March '7, 1946 2 She'gts-Sheet 2 ii i 59 42 1 ii a l@ i i 2 2s v 23 "1 as 7 as 84 5 4 l j as 33 f Inventor 14 10; ffa/z 72 Mm WWW Em Patented May 18, 1948 "snocn ABSORBER Melvin ah Lawr nc bu Kit, s i n r Prof foneehalf toForrestn'nahn, GincinnatiiiQhio Application" March "7, 1946,.'Serial No. 1652:! 36

This invention relates to a shock absorber for use between the axle and frame of a vehicle and has for itspri-mar y obl'eet to eontrol the -rebound betweenthe ira-me andthe axle of the-vehicle commonly encountered When-the *vehiole strikes cover, 1 a'--spring surrounding the"cylinder and -pi-ston rod and yi'eIdingly 'e'ngaging the axle and frame of the vehicle-tof hold -the p'ar-ts in spaced relation, valves in the headfor establishing communication -between =the reservoirand the 'cylin der when the piston rnovesjdownwardly therein, valves in the piston for est'a'blishing communication between the upper andlovver ends of the cylinder as the piston moves 'upwardly therein, and means establishing communication between the lower =end-of the;'cylinder-and'the reservoir.

Other features include a "valve in *the' passage which establishes communication between the bottom of 'the cylinder and the reservoir operable to open said passage when "the piston moves downwardly.

In the drawings;

Figure 1 is a side view of ashock absonberembodying the features .of sthis invention showin the sameinpositiombetween an axle and a side bar of the chassis of the vehicle,

Figure 32 .is an enlarged longitudinal sectional view through the shock absorber,

*Eigure is .a ehorizontal seetional View. taken substantially along thedine 3-3; of Figure 2, and

Figure 4 is a horizontal sectional view taken substantially along ma med-+4 of Figure}2 net rnn to the-drawings in-detail theaxle IE! of a conventional vehicle is arra n-ged to support the frame II in spaced relation therewith in the conventional manner so as to permit relative movment between the two when a rough spot is encountered in the roadway over which the vehicle may be travelling. Supported on the axle It is my improved shock absorber designated generally I2 which comprises a cylinder l3 having an axial bore I 4 upon opposite sides of which are arranged longitudinally extending by-pass passages l5 which are coextensive with the cylinder. The upper ends of the bore 14 and the by-pass eZ-tQIaimS. (c1. sci-s) '2 .passagesrH-are wholly open; Extending radially through the bot-tomfind IB of the cylinder are passages 1 If! whichcommunicate with the hi -pass ssa s 5, and .withe-anvon ins o m d an 'ia'llvinit e bott m wall; I26- Mounted for reciprocal motion: inthe bore l 4 of the cylinder 13 1s :a :piston l9-to which a-piston rod is attachedand this; piston rod rises axiallvh u h h c lin to v -1 .121 8 n attached asbyqbelts =2-l-tothe frame 1;! ofthe vehicle. ,It will thus beseen-that .whenthere-is relative "movement-between the axle l0 -and' the frame vll .thepistondfi will bereciprocated within the bore M, of the cylinder l3.

-'.Closing the open-uppergend of-the'cylinder bore i4 is a head v22 ,provided with-passages 2-3 which align with the-,bvpass passages has willbe, readily understood .upon reference to Figure -2. Formed atsuitably-spacedpointsin the head 22 (are openings-24 for the receptionof check-valves .25 normally heldin-closedposition by compression; springs 7-25. These valves. 25 i are so arranged as t to open 1 when the piston I 9 moves downwardly tin the cylinder, andltheir purpose will more fully hereinafte appear. Thel-headlz-is providedwith ,an'axialopening 2 6 ,forthe reception of-thepis- "ton rod .20 land a suitable-packing gland 21 is arranged to surround the piston rod in order to ,form a,fluid tight jointqbetween-therod and head. -.A hollow'eylindricallcover28 =15 mounted atop .the-,.head 22 and form-s a fluid storage reservoir which communicates with the passages l5 through the openings 23 in the head 22. Like theheadll-the endwallof the cover28is formed withan axial. opening 23 through which thepiston rod :20" extendsliand surrounding the piston rod is aIpacklnggIandBD which servesto prevent the;=escape of fluid from the interior of the vfluid reservoira'roundthe pistonrod.

Eormed atspaced intervals in the piston 13 are passages or ,port's 32 carrying {at their upper ends valve seats 33 for engagement with check valves 34 which are normally held ,in closedpositio bygcompression springsl35" As'showmthe upper ends of the springs 35 bear ag'ains't'the undersides of the valves 34 while the lower ends of the springs 35 rest on collars 36 which are entered into the lower ends of the ports 32 and are provided with relatively small passages 31 which serve to retard the flow of fluid from one side of the piston to the other, and hence retard the elevation of the piston within the cylinder. A check valve 38 is mounted in the axial bore l3 and operates in such a manner that when the piston I9 descends in the cylinder, the fluid on the upper end of the piston rod near its junction with the frame II and serves as a buffer.

In operation it will be understood that when a rough spot is encountered in the. roadway over which the vehicle may be travelling the axle ID will be driven upwardly toward the frame I I, thus causing the cylinder l3 to rise against the piston l9. Fluid having been introduced into the reser: voir through the medium of the opening 42 in the cover 28 will cause the check valves 25 to open against the compression of the springs 26 as to permit the fluid to flow through the ports 24 and into the upper end of the bore l4 above the piston l9. Any fluid which may be contained in the space between the bottom l6 of the cylinder l3 and the piston I9 will 'be forced outwardly through th'e check valve 38, the radial passages H, the by-pass passages 5 and the openings 23 in the head 22, into the reservoir formed by the cap member 28. It will thus be seen that the telescopic motion between the cylinder and the piston will refill the reservoir so asto maintain an adequate supply of fluid on the upper side of the head 22. Naturally themovement of th'e axle l toward the frame member I will compress the spring 40 and while under such compression this spring will endeavor to force the parts away from one another, and thereby exert pull on the piston rod to cause the piston to rise in the cylinder against the fluid that has been drawn into the cylinder through the check valves 25. The return of the parts to their initial position is effected through the automatic opening of the check valves 34 and the escape of the fluid from the upper side of the piston to the lower side'thereof through the passages 31. Obviously by regulating the size of these passages, as by substituting bushings 36 having different sized openings 31 therein, the speed with which the parts return to their initial positions may be regulated, It will be understood of course that the shock absorber is to be installed on the vehicle after the speed of rebound of the spring system has been determined, so that the proper bushing 36 may be selected in accordance with the spring reaction.

While in the foregoing there has been shown and described the preferred embodiment of this invention it is to be understood that minor changes in the details of construction, combination and arrangement of parts may be resorted to without departin from the spirit and scope of the invention as claimed.

What I claim is:

1. A shock absorber comprising a vertically dis- .4 posed cylinder adapted to be attached ot the axle of a vehicle, a piston operable in the cylinder, a head closing the upper end of the cylinder, a piston rod connected to the piston and extending axially through the head, the upper end of the rod being adapted to be attached to the frame of the vehicle, a spring encircling th'e cylinder and rod and engaging the axle and frame yielding to hold the axle and frame in spaced relation, a hollow cap supported on the head having an axial opening through which the piston rod works, said cap cooperating with the head in forming a fluid resvalves in th'e head establishing communication between the reservoir and cylinder when the piston is moved against the force of the spring, check valves in the piston establishing communication through the piston when it is moved in the opposite direction and means establishing communication between the lower end of the cylinder and the reservoir when the piston is moved against the spring.

2. A shock absorber comprising a vertically disposed cylinder adapted to be attached to the axle of a vehicle, a piston operable in the cylinder, a head closing the upper end of the cylinder, a piston rod connected to the piston and extending axially through the head, the upper end of the rod being adapted to be attached to the frame of the vehicle, a spring encircling th'e cylinder and rod and engaging the aXle and frame yielding to hold the axle and frame in spaced relation, a hollow cap supported on the head having an axial opening through which the piston rod works, said cap cooperating with the head in forming a fluid reservoir at the upper end of the cylinder, check valves in the head establishing communication between the reservoir and cylinder when the piston is moved against the force of the spring, check valves in the piston establishing communication through the piston when it is moved in the opposite direction, the wall of the cylinder and the head having by-pass passages therein establishing communication between the lower end of the cylinder and the reservoir and a check valve operable to open said by-pass passages when the piston is moved against the force of the spring.

' MALVIN HAHN.

' REFERENCES CITED The following references are of record in the file of this patent:

UNITED s'rA'rEs PATENTS 

